| 摘要 |
<p>A peak hold circuit and a sample-and-hold circuit are provided for accurately and immediately detecting variations in a load connected to a generator. The peak hold circuit holds a peak voltage of a waveform voltage signal having an amplitude corresponding to the magnitude of the load. The peak hold circuit is responsive to a reset signal from a reset circuit to be reset during a time interval between a point after the peak of the waveform voltage signal and a point before a subsequent peak of the waveform voltage signal, so that the peak hold circuit is reset, thereby renewing the peak voltage held in the peak hold circuit. When the sample-and-hold circuit receives a sampling instruction signal from a sampling instruction circuit during a time interval between a point after the peak of said waveform voltage signal and a point before said reset signal is outputted, the sample-and-hold circuit operates in a sampling mode to sample the peak voltages outputted from the peak hold circuit. The sample-and-hold circuit is switched into a hold mode before the peak hold circuit is reset, so as to hold the sampled peak voltage.</p> |
